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The Texas Petawatt Laser

Posted by kdawson on from the you-can-pet-a-dog-or-you-can-pet-a-cat dept.

Roland Piquepaille notes the hype surrounding what the University of Texas at Austin is calling the world's most powerful laser. During a tenth of a femtosecond this laser is 2,000 times more powerful than all the power plants in the US, and is brighter than sunlight on the surface of the Sun. On his own blog Roland points out that UT's is not the first petawatt laser; that distinction belongs to a system installed at Lawrence Livermore National Laboratory in 1996.

15 of 174 comments (clear)

  1. We're all wondering... by dj_tla · · Score: 5, Funny

    Will this laser have to be attached to significantly more powerful sharks?

    1. Re:We're all wondering... by Icarium · · Score: 4, Funny

      Wouldn't firing this laser underwater make the water uncomfortably hot? Please people, think of the sharks!

    2. Re:We're all wondering... by odourpreventer · · Score: 4, Informative

      Where do they get the power to run this thing anyway?

      In case this was a serious question: Giant capacitors, connected in parallel.

      --
      Adventure, Romance, MAD SCIENCE!
    3. Re:We're all wondering... by Tribbin · · Score: 4, Funny

      It will look a little like this:

      http://upload.wikimedia.org/wikipedia/en/d/d3/BFG9000doom2.jpg

      --
      If you mod this up, your slashdot background will turn into a beautiful sunset!
    4. Re:We're all wondering... by yoavi · · Score: 5, Informative

      This is not accurate. Watts are indeed rates of energy consumption, that is, the amount of energy consumed per unit time (Watt stands for Joule per second). Now, if we squeeze 100 Joules in into 10^-13 of a second, then the *instantaneous* power during those 100 femtoseconds (and yes, the story has got it wrong, it's a tenth of a picosecond, not femtosecond, which makes a hundred femtoseconds) is one petawatt. The average power, assuming we operate at 0.1Hz (which I think will be the laser's repetition rate) is only 10 Watts.

      This also answers the "heating" problem. These lasers carry a relatively small amount of energy, and produce very little heat. However, the electric field that is produced when the beam is focused is huge, and many interesting phenomena can be studied with such a laser.

      Btw, for the same reason, this type of laser is completely useless as a weapon. In order to cause any real damage one has to deposit energy into the substance that is to be damaged, and again, these laser pulses carry a relatively small amount of energy.

    5. Re:We're all wondering... by The+Bender · · Score: 4, Informative

      Obviously the energy is built up over the period between pulses. And since the repetition rate is only 1 shot per HOUR, the average power output is only 0.1 W!

      That wouldn't even put a dent in my electricity bill.

      Yes I know, I know...

  2. Sorry boys by martin-boundary · · Score: 4, Funny

    It'll never work. There's just no peta tonne shark to put it on.

  3. link to project page by dermond · · Score: 4, Informative

    http://www.ph.utexas.edu/~utlasers/texas_petawatt_files/texas_petawatt.htm

    with fotos and shematics, etc..

  4. But... by Rix · · Score: 4, Funny

    Can it levitate a squirrel?

  5. Wrong about the Sun and petawatts by Ancient_Hacker · · Score: 4, Informative
    A petawatt is only 10^15 watts.

    Our Sun puts out about 4 x 10^24 watts, continuously, for billions of years.

    So this laser is only putting out about one four-billionth of the Sun, and only for a very split second.

    It's also very misleading if they intended to compare brightness per unit area. Even a cheap laser pointer is brighter than the surface of the Sun.

  6. Obvious mistake in TFA by justkeeper · · Score: 5, Informative

    One femtoseocnd is 10 to the power of -15 of a second,NOT one trillionth of a second.Thus the pulse duration should be 100 fs,which is realistic.State of the art technology can't yet produce high power sub-femtosecond(i.e attosecond) pulses ,due to low conversion efficiency of energy concentrated on the low-frequency spectrum to the high-frequency spectrum using currently available methods(for an attosecond pulse a Fourier Transform will show that you have mostly X-ray frequency components in the frequency spectrum). Discaimer:I'm a Ph.D student working on high-power laser systems.

  7. Soon to be a Dime a Dozen by djtachyon · · Score: 5, Informative

    University of Rochester is building a petawatt laser of capable of picosecond pulse lengths. http://omegaep.lle.rochester.edu/

    --
    "What's the use of a good quotation if you can't change it?" - Doctor Who
  8. Re:Time duration? by MLCT · · Score: 4, Informative

    They aren't ridiculous - and you are ill informed to say that they are. Average power vs. peak power. Those two variables are highly relevent for a pulsed laser. Your "torch" isn't even pulsed.

    A lot of ground breaking research is undertaken *utilising* the ability to deliver very short very high energy pulses - for doing that you can deliver a huge amount of energy in a very tiny amount of time - then observe what happens. Indeed a lot of the very high energy regions cannot be accessed with anything but ultrafast pulsed systems, as CW setups would just destroy themselves (and even using UF systems chirping "tricks" are used to reduce peak powers until the final moment to ensure the optics aren't burnt out).

    See http://en.wikipedia.org/wiki/Chirped_pulse_amplification

  9. Roland the Plogger again by Animats · · Score: 4, Informative

    More Roland the Plogger blogspam, driving traffic to his useless ad-laden blog. To get around the block on links to his own site, he's now submitting links disguised via "tinyurl".

    Slashdot covered this laser weeks ago.

  10. Correction: by JSBiff · · Score: 4, Funny

    "Don't Lase me, Bro!"

    Fixed it for you.